The invention relates to a sampler for taking samples from melts having a melting point higher than 600° C., in particular for metal or cryolite melts, especially iron or steel melts. The sampler comprises a carrier tube having an immersion end and having a sample chamber assembly arranged on the immersion end of the carrier tube. The assembly has an inlet opening and a sample cavity for the melt and is arranged at least partially inside the carrier tube. In addition, the invention relates to a sample chamber assembly for such a sampler and to a method for taking samples using such a sampler.
Numerous samplers for melts, in particular for metal or cryolite melts, are known. For example, German Patent DE 32 33 677 C1 describes a sampler for metal and slag. Here, on the immersion end of a carrier tube there is provided an inlet opening for a sample cavity, which is covered by a protective cap. Similar samplers are known from European patent application publication EP 1 544 591 A2 or from German published patent application DE 25 04 583 A1.
From German Patent DE 10 2005 060 492 B3 a combination is known of a sampler and sensors for measurement in metal or slag melts. Here, a measurement head is disclosed for accommodating the sensors, additionally having on its immersion end an inlet opening for a sample cavity.
These samplers have in common that the sample cavity is arranged on the immersion end of a carrier tube intended for immersion in the melt, whereby after the taking of the sample and the withdrawal of the carrier tube from the melt, the immersion end with the sample cavity is separated from the carrier tube, and the sample is subsequently removed from the sample cavity and delivered to an analysis device. Further similar arrangements are disclosed, for example, in U.S. Pat. No. 6,113,669.
Carrier tubes are described, inter alia, in European patent application publication EP 143 498 A2 and U.S. Pat. No. 4,893,516. Here it is also disclosed that the carrier tube is attached to a lance for the measurement or taking of samples. The lance serves for the automated machine handling or manual handling of the carrier tube having the sample cavity or the sensors. Using the lance, the carrier tube is immersed in the metal melt and withdrawn from it. The carrier tube having the sampler or sensor equipment is a disposable article, which is disposed of after being used once, while the lance (also designated carrier lance) is used multiple times.
The lance is used not only for the immersion of the carrier tube, but also to transmit signals via the signal cable routed through the lance. The lance is connected to the carrier tube by a so-called coupling piece, wherein signal cables or other functional units may also be integrated in the coupling piece. Corresponding contacts, with whose aid a transmission of signals through a carrier lance takes place, are represented, inter alia, in German Patent DE 10 2005 060 492 B3.
In the known samplers, the removal of the sample from the sample cavity takes place immediately after withdrawal of the carrier tube from the metal melt, whereby the immersion end of the carrier tube and the sample cavity themselves are destroyed while releasing the sample arranged in the sample cavity. For this purpose, the carrier tube can be simply dropped onto the floor next to the melt container, so that the carrier tube, which is damaged anyway during the immersion process and as a rule is made of cardboard, falls apart and releases the sample. Sample cavities for hot melts, such as metal melts, are often formed from two-part sample chamber assemblies, so that the two parts fall apart from one another and release the sample. In particular with high-temperature melts, such as steel melts, the sample itself is still very hot when it is exposed to the ambient air by opening the sample cavity. As a result, the surface of the sample can oxidize, so that a post-treatment of the sample is required before analysis. From German published patent application DE 25 04 583 A1 it is also known to pull the sample chamber assembly out through the protective housing.